A quick note. The black calibration of the SI2K camera can put your camera into a funny state, if Black Calibration is performed when one, or both lens caps are off. You may end up with a black image, and bright edges. Similar to the "Glowing Edges" effect in Photoshop.
To correct this you must put the lens caps back on and redo your black calibration.
The example image is borrowed from http://www.flickr.com/photos/43439500@N00/828510428